Escalators and moving walkways have long been known. Escalators comprise steps, and moving walkways comprise pallets which are typically guided, by way of two chain rollers and two drag rollers, on rails. Here, the step or pallet is connected in the region of the chain roller to the pallet chain or step chain of the escalator or of the moving walkway, and is also laterally guided there. By contrast, the drag rollers typically run on flat rails without additional lateral guidance.
To ensure smooth running, various measures have become known. For example, for approximately 50 years, the running surfaces of the drag rollers have been coated with rubber or, nowadays, plastic in order to ensure reduced rolling noise. It has also been proposed for the steps or pallets to be sprayed with noise-deadening material from the underside.
Furthermore, in EP 0 169 349 A1, it has been proposed for the roller spindles themselves to be mounted flexibly in a type of silent block. This solution is duly basically effective when the step or pallet is guided over unevennesses on the rail, because the vibrations are dampened in this way. Said approach however has not become established because, in the case of unilateral loading of said step, the step sinks downward there and accordingly comes dangerously close to the balustrade, to the point of grinding against the balustrade or even carrying the balustrade along.
If it is intended to prevent this, it is duly possible for the gap between the step or pallet and the balustrade to be increased, for example to 15 mm. This is however undesirable and is objectionable from a safety aspect, because then the risk of injury to passengers is even greater.
Various other types of fastening of the drag rollers to the steps are also provided. A mechanically expedient solution is presented in GB 1 373 795. In said document, the steel spindle of the drag roller is cast into the light-metal body of the step. Such a step is however highly cumbersome to produce.
Furthermore, DE 203 01 358 U1 has disclosed a mounting of a step by way of screwed bearing journals secured by locknut, which bearing journals form the roller spindles. Said solution is likewise highly stable and permits a small lateral clearance toward the balustrade.
Owing to the unilateral mounting, said screw connections are subject to considerable moments; the burden is dependent on the load, which is to say generally the number of passengers being transported by the respective step or pallet.